feat(Core/Player): implement Spell Queue (#20797)

src/server/apps/worldserver/worldserver.conf.dist

@@ -2163,6 +2163,21 @@ NoResetTalentsCost = 0
 
 ToggleXP.Cost = 100000
 
+#
+#    SpellQueue.Enabled
+#        Description: Enable SpellQueue.
+#        Default:     0 - (Disabled)
+#                     1 - (Enabled)
+
+SpellQueue.Enabled = 1
+
+#
+#    SpellQueue.Window
+#        Description: Time (in milliseconds) for spells to be queued.
+#        Default:     400 - (400ms)
+
+SpellQueue.Window = 400
+
 #
 ###################################################################################################
 

src/server/game/Entities/Player/Player.cpp

@@ -1026,6 +1026,9 @@ void Player::setDeathState(DeathState s, bool /*despawn = false*/)
             return;
         }
 
+        // clear all pending spell cast requests when dying
+        SpellQueue.clear();
+
         // drunken state is cleared on death
         SetDrunkValue(0);
         // lost combo points at any target (targeted combo points clear in Unit::setDeathState)

src/server/game/Entities/Player/Player.h

@@ -1060,6 +1060,18 @@ struct EntryPointData
     [[nodiscard]] bool HasTaxiPath() const { return taxiPath[0] && taxiPath[1]; }
 };
 
+struct PendingSpellCastRequest
+{
+    uint32 spellId;
+    uint32 category;
+    WorldPacket requestPacket;
+    bool isItem = false;
+    bool cancelInProgress = false;
+
+    PendingSpellCastRequest(uint32 spellId, uint32 category, WorldPacket&& packet, bool item = false, bool cancel = false)
+        : spellId(spellId), category(category), requestPacket(std::move(packet)), isItem(item) , cancelInProgress(cancel) {}
+};
+
 class Player : public Unit, public GridObject<Player>
 {
     friend class WorldSession;
@@ -2615,6 +2627,20 @@ public:
 
     std::string GetDebugInfo() const override;
 
+    /*********************************************************/
+    /***               SPELL QUEUE SYSTEM                  ***/
+    /*********************************************************/
+protected:
+    uint32 GetSpellQueueWindow() const;
+    void ProcessSpellQueue();
+
+public:
+    std::deque<PendingSpellCastRequest> SpellQueue;
+    const PendingSpellCastRequest* GetCastRequest(uint32 category) const;
+    bool CanExecutePendingSpellCastRequest(SpellInfo const* spellInfo);
+    void ExecuteOrCancelSpellCastRequest(PendingSpellCastRequest* castRequest, bool isCancel = false);
+    bool CanRequestSpellCast(SpellInfo const* spellInfo);
+
 protected:
     // Gamemaster whisper whitelist
     WhisperListContainer WhisperList;

src/server/game/Entities/Player/PlayerUpdates.cpp

@@ -79,6 +79,7 @@ void Player::Update(uint32 p_time)
 
     // used to implement delayed far teleports
     SetMustDelayTeleport(true);
+    ProcessSpellQueue();
     Unit::Update(p_time);
     SetMustDelayTeleport(false);
 
@@ -2255,3 +2256,89 @@ void Player::ProcessTerrainStatusUpdate()
     else
         m_MirrorTimerFlags &= ~(UNDERWATER_INWATER | UNDERWATER_INLAVA | UNDERWATER_INSLIME | UNDERWATER_INDARKWATER);
 }
+
+uint32 Player::GetSpellQueueWindow() const
+{
+    return sWorld->getIntConfig(CONFIG_SPELL_QUEUE_WINDOW);
+}
+
+bool Player::CanExecutePendingSpellCastRequest(SpellInfo const* spellInfo)
+{
+    if (GetGlobalCooldownMgr().HasGlobalCooldown(spellInfo))
+        return false;
+
+    if (GetSpellCooldownDelay(spellInfo->Id) > GetSpellQueueWindow())
+        return false;
+
+    for (CurrentSpellTypes spellSlot : {CURRENT_MELEE_SPELL, CURRENT_GENERIC_SPELL})
+        if (Spell* spell = GetCurrentSpell(spellSlot))
+        {
+            bool autoshot = spell->m_spellInfo->IsAutoRepeatRangedSpell();
+            if (IsNonMeleeSpellCast(false, true, true, autoshot))
+                return false;
+        }
+    return true;
+}
+
+const PendingSpellCastRequest* Player::GetCastRequest(uint32 category) const
+{
+    for (const PendingSpellCastRequest& request : SpellQueue)
+        if (request.category == category)
+            return &request;
+    return nullptr;
+}
+
+bool Player::CanRequestSpellCast(SpellInfo const* spellInfo)
+{
+    if (!sWorld->getBoolConfig(CONFIG_SPELL_QUEUE_ENABLED))
+        return false;
+
+    // Check for existing cast request with the same category
+    if (GetCastRequest(spellInfo->StartRecoveryCategory))
+        return false;
+
+    if (GetGlobalCooldownMgr().GetGlobalCooldown(spellInfo) > GetSpellQueueWindow())
+        return false;
+
+    if (GetSpellCooldownDelay(spellInfo->Id) > GetSpellQueueWindow())
+        return false;
+
+    // If there is an existing cast that will last longer than the allowable
+    // spell queue window, then we can't request a new spell cast
+    for (CurrentSpellTypes spellSlot : { CURRENT_MELEE_SPELL, CURRENT_GENERIC_SPELL })
+        if (Spell* spell = GetCurrentSpell(spellSlot))
+            if (spell->GetCastTimeRemaining() > static_cast<int32>(GetSpellQueueWindow()))
+                return false;
+
+    return true;
+}
+
+void Player::ExecuteOrCancelSpellCastRequest(PendingSpellCastRequest* request, bool isCancel /* = false*/)
+{
+    if (isCancel)
+        request->cancelInProgress = true;
+
+    if (WorldSession* session = GetSession())
+    {
+        if (request->isItem)
+            session->HandleUseItemOpcode(request->requestPacket);
+        else
+            session->HandleCastSpellOpcode(request->requestPacket);
+    }
+}
+
+void Player::ProcessSpellQueue()
+{
+    while (!SpellQueue.empty())
+    {
+        PendingSpellCastRequest& request = SpellQueue.front(); // Peek at the first spell
+        SpellInfo const* spellInfo = sSpellMgr->GetSpellInfo(request.spellId);
+        if (CanExecutePendingSpellCastRequest(spellInfo))
+        {
+            ExecuteOrCancelSpellCastRequest(&request);
+            SpellQueue.pop_front(); // Remove from the queue
+        }
+        else // If the first spell can't execute, stop processing
+            break;
+    }
+}

src/server/game/Entities/Unit/CharmInfo.cpp

@@ -400,6 +400,22 @@ bool GlobalCooldownMgr::HasGlobalCooldown(SpellInfo const* spellInfo) const
     return itr != m_GlobalCooldowns.end() && itr->second.duration && getMSTimeDiff(itr->second.cast_time, GameTime::GetGameTimeMS().count()) < itr->second.duration;
 }
 
+uint32 GlobalCooldownMgr::GetGlobalCooldown(SpellInfo const* spellInfo) const
+{
+    if (!spellInfo)
+        return 0;
+
+    auto itr = m_GlobalCooldowns.find(spellInfo->StartRecoveryCategory);
+    if (itr == m_GlobalCooldowns.end() || itr->second.duration == 0)
+        return 0;
+
+    uint32 start = itr->second.cast_time;
+    uint32 delay = itr->second.duration;
+    uint32 now = getMSTime();
+
+    return (start + delay > now) ? (start + delay) - now : 0;
+}
+
 void GlobalCooldownMgr::AddGlobalCooldown(SpellInfo const* spellInfo, uint32 gcd)
 {
     m_GlobalCooldowns[spellInfo->StartRecoveryCategory] = GlobalCooldown(gcd, GameTime::GetGameTimeMS().count());

src/server/game/Entities/Unit/CharmInfo.h

@@ -83,6 +83,7 @@ public:
 
 public:
     bool HasGlobalCooldown(SpellInfo const* spellInfo) const;
+    uint32 GetGlobalCooldown(SpellInfo const* spellInfo) const;
     void AddGlobalCooldown(SpellInfo const* spellInfo, uint32 gcd);
     void CancelGlobalCooldown(SpellInfo const* spellInfo);
 

src/server/game/Handlers/SpellHandler.cpp

@@ -85,6 +85,41 @@ void WorldSession::HandleUseItemOpcode(WorldPacket& recvPacket)
         return;
     }
 
+    SpellInfo const* spellInfo = sSpellMgr->GetSpellInfo(spellId);
+
+    if (!spellInfo)
+    {
+        LOG_ERROR("network.opcode", "WORLD: unknown spell id {}", spellId);
+        recvPacket.rfinish(); // prevent spam at ignore packet
+        return;
+    }
+
+    // fail if we are cancelling pending request
+    if (!_player->SpellQueue.empty())
+    {
+        PendingSpellCastRequest& request = _player->SpellQueue.front(); // Peek at the first spell
+        if (request.cancelInProgress)
+        {
+            pUser->SendEquipError(EQUIP_ERR_NONE, pItem, nullptr);
+            recvPacket.rfinish(); // prevent spam at ignore packet
+            return;
+        }
+    }
+
+    // try queue spell if it can't be executed right now
+    if (!_player->CanExecutePendingSpellCastRequest(spellInfo))
+        if (_player->CanRequestSpellCast(spellInfo))
+        {
+            recvPacket.rpos(0); // Reset read position to the start of the buffer.
+            _player->SpellQueue.emplace_back(
+                spellId,
+                spellInfo->GetCategory(),
+                std::move(recvPacket), // Move ownership of recvPacket
+                true // itemCast
+            );
+            return;
+        }
+
     if (pItem->GetGUID() != itemGUID)
     {
         pUser->SendEquipError(EQUIP_ERR_ITEM_NOT_FOUND, nullptr, nullptr);
@@ -341,6 +376,10 @@ void WorldSession::HandleCastSpellOpcode(WorldPacket& recvPacket)
 {
     uint32 spellId;
     uint8  castCount, castFlags;
+
+    if (recvPacket.empty())
+        return;
+
     recvPacket >> castCount >> spellId >> castFlags;
     TriggerCastFlags triggerFlag = TRIGGERED_NONE;
 
@@ -365,6 +404,36 @@ void WorldSession::HandleCastSpellOpcode(WorldPacket& recvPacket)
         return;
     }
 
+    // fail if we are cancelling pending request
+    if (!_player->SpellQueue.empty())
+    {
+        PendingSpellCastRequest& request = _player->SpellQueue.front(); // Peek at the first spell
+        if (request.cancelInProgress)
+        {
+            Spell* spell = new Spell(_player, spellInfo, TRIGGERED_NONE);
+            spell->m_cast_count = castCount;
+            spell->SendCastResult(SPELL_FAILED_DONT_REPORT);
+            spell->finish(false);
+            recvPacket.rfinish(); // prevent spam at ignore packet
+            return;
+        }
+    }
+
+    // try queue spell if it can't be executed right now
+    if (!_player->CanExecutePendingSpellCastRequest(spellInfo))
+    {
+        if (_player->CanRequestSpellCast(spellInfo))
+        {
+            recvPacket.rpos(0); // Reset read position to the start of the buffer.
+            _player->SpellQueue.emplace_back(
+                spellId,
+                spellInfo->GetCategory(),
+                std::move(recvPacket) // Move ownership of recvPacket
+            );
+            return;
+        }
+    }
+
     // client provided targets
     SpellCastTargets targets;
     targets.Read(recvPacket, mover);
@@ -483,6 +552,8 @@ void WorldSession::HandleCancelCastOpcode(WorldPacket& recvPacket)
     recvPacket.read_skip<uint8>();                          // counter, increments with every CANCEL packet, don't use for now
     recvPacket >> spellId;
 
+    _player->SpellQueue.clear();
+
     _player->InterruptSpell(CURRENT_MELEE_SPELL);
     if (_player->IsNonMeleeSpellCast(false))
         _player->InterruptNonMeleeSpells(false, spellId, false, true);

src/server/game/Spells/Spell.h

@@ -551,6 +551,7 @@ public:
     bool IsAutoRepeat() const { return m_autoRepeat; }
     void SetAutoRepeat(bool rep) { m_autoRepeat = rep; }
     void ReSetTimer() { m_timer = m_casttime > 0 ? m_casttime : 0; }
+    int32 GetCastTimeRemaining() { return m_timer;}
     bool IsNextMeleeSwingSpell() const;
     bool IsTriggered() const { return HasTriggeredCastFlag(TRIGGERED_FULL_MASK); };
     bool HasTriggeredCastFlag(TriggerCastFlags flag) const { return _triggeredCastFlags & flag; };

src/server/game/World/IWorld.h

@@ -183,6 +183,7 @@ enum WorldBoolConfigs
     CONFIG_ALLOWS_RANK_MOD_FOR_PET_HEALTH,
     CONFIG_MUNCHING_BLIZZLIKE,
     CONFIG_ENABLE_DAZE,
+    CONFIG_SPELL_QUEUE_ENABLED,
     BOOL_CONFIG_VALUE_COUNT
 };
 
@@ -419,6 +420,7 @@ enum WorldIntConfigs
     CONFIG_WATER_BREATH_TIMER,
     CONFIG_AUCTION_HOUSE_SEARCH_TIMEOUT,
     CONFIG_DAILY_RBG_MIN_LEVEL_AP_REWARD,
+    CONFIG_SPELL_QUEUE_WINDOW,
     INT_CONFIG_VALUE_COUNT
 };
 

src/server/game/World/World.cpp

@@ -1487,6 +1487,10 @@ void World::LoadConfigSettings(bool reload)
     // Realm Availability
     _bool_configs[CONFIG_REALM_LOGIN_ENABLED] = sConfigMgr->GetOption<bool>("World.RealmAvailability", true);
 
+    // SpellQueue
+    _bool_configs[CONFIG_SPELL_QUEUE_ENABLED] = sConfigMgr->GetOption<bool>("SpellQueue.Enabled", true);
+    _int_configs[CONFIG_SPELL_QUEUE_WINDOW] = sConfigMgr->GetOption<uint32>("SpellQueue.Window", 400);
+
     // call ScriptMgr if we're reloading the configuration
     sScriptMgr->OnAfterConfigLoad(reload);
 }